The design is based on the Soviet design. It is supposed to have some kind of staging in the combustion chamber to get a better specific impulse.
Watching the video, my first impression was a turbo pump failure, maybe on the liquid oxygen. There was still a flame, but only due to fuel running. Thus loss of thrust causing the rocket to fall back on the pad. Somewhat like some of the test failures during the late fifties (the old Atlas and Thor test flights).
LOX blowout somewhere, loss of thrust due to no chamber pressure, fall to pad, explosion of whatever was in the supply lines, venting and ignition of a tank somewhere...destruction of millions of $ of equipment.
SPACEX had a very similar-looking but more violent incident on an earlier launch (but later in flight) and still made the supply mission. Makes you go hmmmmmm.